Defibrillation and functionalization of cellulose fibers from different sources in one-step via a mechanochemical method

Mechanochemical methods for cellulose processing have gained significant attention for the higher efficiency and the potential for special applications. Cellulose pulp fibers from different sources including softwood, hardwood and bamboo were selected as starting materials in this study, because the performance and sustainability of cellulose based materials are highly dependent on their sources. They were successfully defibrillated and functionalized in one-step by 3-aminopropyltriethoxysilane (APTES)-assisted ball milling method. The morphology, chemical structure and crystal structure of the cellulose fibers before and after modification were characterized. Translucent cellulose films with high haze (about 94.8%) were prepared through vacuum-assisted filtration. The test results show that the addition of APTES plays a significant role in enhancing the performance of cellulose films, not only weakening the hydrophilicity (water contact angle of up to 88°), but also enhancing the transparency (transmittance of up to 78%), thermal stability and mechanical properties. These demonstrate that the APTES-assisted ball milling method is an effective way to tailor the structure of cellulose fibers due to its easy operation and wide applicability. In addition, softwood and bamboo films that show relatively higher comprehensive performance on the radar chart have higher application value in the packaging, composite materials and other fields. This work provides guidance for the design and efficient preparation of high-performance cellulose materials. Graphical abstract